Acorn, I think the thing lacking is independent critical analysis and risk review. The current SA situation shows what a 50% renewable supply looks like. Our NEM is an island, unlike O'seas countries we don't have external interconnectors to rely on so we must at all times have sufficient reserve to cover all eventualities including extreme weather events and unfavourable weather events if we are planning to rely on weather dependent resources.
The data from this week enables anyone to test the current theory and policy settings. Installed capacity is fixed, SA has significant Wind and Solar and also some small battery capacity. They also have large Gas generation capacity which they are planning to close and rely on imports as per the OP.
This week they have operated at around 50% renewable consistently, that is an achievement in itself. To achieve 50% reliably and protect their energy supply some additional constraints have been introduced. The constraints mean the excesses / deficits cannot be hidden.
In the week of 1st Feb to 7th Feb the Rooftop Generated 40 GWh (Roughly 28% Capacity Factor) Utility Solar 7 GWh (Roughly 18% CF) and Wind 76 GWh ( 30% CF). Curtailment was 27 GWh with peak being 712 MW's. The highest day was the 5th when 5,675 GWh of Utlity Solar & Wind was curtailed. Overall the curtailment factor was 18% of available Utility Solar and Wind which is significant. If this is indicative of a 50% Policy then I think we have a problem with the current LCOE calculations which ignore constraints. Also rooftop is displacing utillity solar/wind which raises questions about the emissions gains that have been claimed. From the curtailment numbers we can calculate the storage required.
All up interesting stuff which as best as I can see is being ignored in the current national discussion.
